Sponge



FIG. 1 is a perspective view of our new design for a sponge shown in a state of use;

FIG. 2 is another perspective view showing the claimed design in a second state of use thereof;

FIG. 3 is a bottom perspective view showing our new design for a sponge;

FIG. 4 is a top perspective view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a top plan view thereof; and

FIG. 7 is a left side elevation view thereof, the right side being a mirror image thereof; and,

FIG. 8 is a front elevation view thereof, the rear being a mirror image thereof.

The broken lines in the drawings illustrate environmental structure that form no part of the claimed design. 

CLAIM The ornamental design for a sponge, as shown and described. 